William Emil Hess (February 13, 1898 – July 14, 1986) was an American lawyer and politician who served three lengthy, non-consecutive stints as a Republican and a U.S. Representative from Ohio between 1929 and 1961.

He was elected as a Republican to the Seventy-first and to the three succeeding Congresses (March 4, 1929 – January 3, 1937); unsuccessful candidate for reelection in 1936 to the Seventy-fifth Congress.

He resumed the practice of law; elected to the Seventy-sixth and to the four succeeding Congresses (January 3, 1939 – January 3, 1949); from early 1940 until the attack on Pearl Harbor, Hess was an interventionist and advocated helping the United Kingdom in the second world war.

Hess was an unsuccessful candidate for reelection in 1948 to the Eighty-first Congress; elected to the Eighty-second and to the four succeeding Congresses (January 3, 1951 – January 3, 1961); was not a candidate for renomination in 1960; resumed the practice of law; was a resident of Cincinnati, Ohio, until his death there on July 14, 1986; interment in Spring Grove Cemetery.

Hess voted in favor of the Civil Rights Acts of 1957 and 1960.